Herbicide composition

Abstract

The present invention relates to a method of selectively controlling weeds at a locus comprising crop plants and weeds, wherein the method comprises application to the locus of a weed controlling amount of an aqueous spray composition comprising a compound of formula (I) wherein R 1 is selected from the group consisting of C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 haloalkenyl, C 2 -C 6 alkynyl, C 2 -C 6 haloalkynyl, C 3 -C 6 cycloalkyl, C 1 -C 6 haloalkyl, C 1 -C 4 alkoxy-C 1 -C 4 alkyl and C 1 -C 4 alkoxy- C 1 -C 4 alkoxy-C 1 -C 4 alkyl; and R 2 is C 1 -C 6 haloalkyl; or an agriculturally acceptable salt therefore; wherein in the pH of the spray composition is from about 5 to about 9. The invention further relates to a liquid substantially non-aqueous herbicide composition comprising a compound of formula (I) as defined above and a pH adjuster, and to the use of a pH adjuster to reduce the phytotoxicity of a compound of formula (I) in crop plants.

The invention claimed is: 
     
       1. A method of improving the selective weed control of a compound of formula I, at a locus comprising crop plants and weeds, wherein the method comprises application to the locus of a weed a controlling amount of an aqueous spray composition comprising (i) 200-400 g/ha of the compound of formula I 
       
         
           
           
               
               
           
         
         wherein R 1  is methoxy-ethoxy-methyl-; and R 2  is CF 3 ; or an agriculturally acceptable salt thereof, (ii) an optional additional pesticide, and (iii) a pH adjuster, wherein the pH adjuster is triethanolamine or diethanolamine; and wherein the pH of the spray composition is from about 5 to about 8; and wherein the pH adjuster within the aqueous spray composition decreases the phytotoxicity of the compound of formula I to the crop plants. 
       
     
     
       2. The method according to  claim 1 , wherein the aqueous spray composition comprises the additional pesticide. 
     
     
       3. The method according to  claim 2 , wherein the additional pesticide is a herbicide selected from the group consisting of ametryn, terbuthylazine, atrazine, alachlor, acetochlor, fomesafen, mesotrione, dicamba, nicosulfuron, rimsulfuron, hexazinone, metolachlor, S-metolachlor, glufosinate and glyphosate. 
     
     
       4. The method according to  claim 1 , wherein the crop plant is selected from the group consisting of cereals, cotton, oilseed rape, maize, rice, soybeans, sugar beet and sugar cane. 
     
     
       5. The method according to  claim 4 , wherein the crop plant is COM. 
     
     
       6. The method according to  claim 1 , wherein the application is made post-emergence of the crop. 
     
     
       7. A liquid herbicidal composition having less than 5% v/v water comprising:
 (a) a compound of formula I 
 
       
         
           
           
               
               
           
         
         
           wherein R 1  is methoxy-ethoxy-methyl-; and R 2  is CF 3  or an agriculturally acceptable salt thereof, said compound of formula I being present in an amount ranging from about 80 to about 300 g/L of said liquid herbicidal composition; and 
         
         (b) an optional additional pesticide; and 
         (c) a pH adjuster, wherein the pH adjuster is triethanolamine or diethanolamine; wherein the pH adjuster is present in the liquid herbicidal composition in an amount effective for providing a spray composition having pH of from about 5 to about 8 when the liquid herbicidal composition is combined with water and/or an aqueous solution. 
       
     
     
       8. The liquid herbicidal composition according to  claim 7 , which is an emulsifiable concentrate. 
     
     
       9. The liquid herbicidal composition according to  claim 7 , which comprises the additional pesticide. 
     
     
       10. The liquid herbicidal composition according to  claim 9 , wherein the additional pesticide is a herbicide selected from the group consisting of ametryn, terbuthylazine, atrazine, alachlor, acetochlor, fomesafen, mesotrione, dicamba, nicosulfuron, rimsulfuron, hexazinone, metolachlor, S-metolachlor, glufosinate and glyphosate. 
     
     
       11. The liquid herbicidal composition according to  claim 9  further comprising a herbicide safener.